Filter press



oct. 31, 1939. v us 2,178,416

FILTER PRESS Filed March 5, 193'? 6 Sheets-Sheet l Q INVENTOR Oct. 31, 1939. A, L, BAUSMAN 2,178,416

FILTER PRESS ATTORNEYS 99 {till 4 74m;

Oct. 31, 1939. I A. BAUSMAN 2.178.416

FILTER PRESS Filed March 5, 1937 6 Sheets-Sheet 3 ATTORNEYS- Oct. 31, 1939.

A. L. BAUSMAN FILTER PRESS Filed March 5, 1937 6 Sheets-Sheet 5 OR Ala/r20 L/MmBAw/m/y fiaw M ATTORNEYS Patented Oct. 31, 1939 UNETED STATES I widths FAEENT @FMQE 16 Claims.

This invention relates to improvements in filter presses, such as are used for the purpose of separating the liquid constituents from the solid constituents of materials in a semifiuent state.

An example of one use of the press is in extracting cocoa butter from cocoa liquor, leaving as a solid residue cocoa in the form of cakes.

The invention has for an object the provision of a press of this character which is substantially automatic in its operation, eliminating much of the manual labor formerly necessary and particularly the manual labor required to empty the press at the end of one operation and re-' condition it for a subsequent operation and, by so doing, reducing to a negligible minimum the time interval between successive operations of the press.

More particularly, the invention has for an object the provision of improved means whereby the several filter-carrying members may be spread apart, after a pressing and filtering operation of the press, and uniformly spaced apart preparatory to removal of the pressed cocoa cakes.

Another object of the invention is to provide improved means for moving the collector rings to cause each to be telescoped over one of the filtercarrying members with which it cooperates, whereby to strip the pressed cakes from the rings and allow them to drop between the spreadapart, filter-carrying members.

Another object is to provide improved means for mounting and operating the spacer fingers, which are used to prevent relative movement of the filter carrying members and the collector rings during the operation of filling the press.

Other objects will appear as the detailed description proceeds and will be pointed out in the appended claims.

The invention will be disclosed with reference to the accompanying drawings, in which:

Fig. 1 is a small-scale plan View of a press embodying the invention, certain link blocks, which are illustrated in Figs. 3, 6 and '7, being omitted so as not to unduly complicate the illustration;

Fig. 2 is a side elevational View thereof;

Fig. 3 is a cross sectional view taken on the line 3-3 of Fig. 1, with parts broken away for clearness of illustration;

Fig. 4 is a cross sectional View taken on the line tii of Fig. 1 with parts in elevation for clearness of illustration;

Fig. 5 is a sectional view taken on the line 5-5 of Fig. 4;

Fig. 6 is a fragmentary sectional plan View taken on the line li6 of Fig. 2;

Fig. 7 is a fragmentary sectional elevational View taken on the line l--l of Fig. 6;

Fig. 8 is a fragmentary cross sectional View taken on the line 88 of Fig. 3;

Fig. 9 is a fragmentary cross sectional View taken on the line 99 of Fig. 2;

Fig. 10 is a top plan View, partly in section, of the safety valve; 1 Fig, 11 is a sectional view taken on the line H--H of Fig. 1; and

Fig. 12 is a fragmentary plan view showing a detail of the mounting of the spacing fingers.

Referring to these drawings and first to Figs. 1 and 2 thereof, the press proper includes fixed heads 20 and 2t, interconnected by two laterallyspaced, longitudinally-extending horizontal bars 22 which maintain the two heads longitudinally spaced one from another. The heads 26 and 2i are supported at the desired level above the floor by suitable standards 23 and M, respectively, to which the heads are suitably fixed. The head 28 is the pressure head and is formed interiorly with a cylinder .25, the left hand end of which is closed and. in which is slidably mounted a ram, having a piston portion 26 with packings 2? for sealing engagement with the peripheral wall of the cylinder and a hollow barrel-like part 28 which extends out of the cylinder toward the head 2i through a removable cylinder head 29 secured as indicated in Fig. 4 by bolts 39 to head 20. The barrel 28, where it passes through head 29, is sealed by packing 3i mounted in a groove in the head. Secured to the outer end of the barrel 28 of the ram (as by a series of bolts 32 indicated in part in Figs. 4 and 6) is a follower or pressure abutment 33 in the form of a large block of substantially square cross section. Liquid, such as oil under pressure, may be admitted to either end of cylinder 25 to move the ram in either direction. For moving the ram on its forward stroke (toward head 2!), liquid is ad mitted to the left hand end of cylinder 25 while the right hand end thereof is connected to exhaust. The liquid under pressure then acts on the full cross sectional area of piston 26 to produce the heavy total pressure required for the pressing operation. For the return stroke, liquid under pressure is admitted to the right hand end of cylinder 25 while the left hand end thereof is connected to exhaust. The effective area of the right hand face of piston 26 is relatively small and a much lower but sufficient total pressure is developed to return the ram after the pressing operation.

Each tie bar 22 has T-heads 3d, one at each end thereof, with which the outer ends of the heads 20 or 2 l, as the case may be, abut, whereby the heads are held against spreading apart. Each head 26 or 2!, as the case may be, is provided on opposite sides with slots, into which portions of the tie bars fit, and the bars are held in place in these slots by plates 35, secured to the head by screws 36. The portions of each tie bar which are received in the aforesaid slots, are of less width than the portions which extend between the two heads, thus affording shoulders 31 for engagement with the inner and adjacent ends of the heads 2!] and 2! to prevent them from being drawn toward one another.

Fixed to the inner face of each tie bar 22 by a series of cap screws 38 (Fig. 3) is a horizontal rail 39 having a flat upper face. These rails 39 serve as trackways for rolls 49 carried by the follower 33, one on each of two opposite sides thereof, whereby the forward end of the ram is supported and guided and held against turning about its axis. These rails further serve as trackways to support and guide four rows of link blocks (Figs. 3 and 6), the blocks of the outer row being marked 4 l, those of the next adjacent row 42, those of the next row 43 and those of the innermost row 44. These blocks are best shown in Fig. 6. Each of these blocks has a tongue 45 depending from its otherwise flat bottom face and the upper face of each rail is provided with four parallel longitudinal grooves 46, one for each series of link blocks, to receive the tongues 45 thereof. Each block is mounted to slide on its trackway in a direction longitudinally of the press. Each rail 38 (Fig. 6) extends from the pressure head 20 to the resistance head 2! and a portion 47 of reduced width (sufficient only for the two outermost rows of link blocks) extends along the head 2| to the outer end thereof, being received in a groove 41' which lies in back of the adjacent tie bar 22.

The links H and 42 are identical in form and dimensions. The links A3 and M are identical in form and dimensions and they differ from links 4! and 42 only in dimensions. Each link has two longitudinally-spaced notches of rectangular form each extending from the upper face of the link downwardly. The bottom of each notch is flat and horizontal and lies in a horizontal plane which passes through the center line of the press, i. e., the center line of ram 26. One notch in each link is longer than the other. The short and long notches of links M are designated as .38 and 49, respectively; those of links 62 as 50 and 5!; those of links 43 as 52 and 53; and those of links M as 54 and 55. These link blocks serve to support the press units (next to be described) acting as weight-bearing shoes or runners which are slidable on the rails 39. They also have other important functions which will later be described.

The press units, of which twenty are herein shown in Fig. 1, are mounted in coaxial relation and in the form of a horizontal column between the follower 33 and a cylindrical abutment 56 on the inner end of the resistance head 2!. This series of units lies between the tie bars 22 and, as mentioned, are supported on opposite sides from the rails 3% on the tie bars through the intermediary of the links, above described. Each press unit comprises a plate 51 (Fig. 6), a disc 58 fixed thereto and an annular ring 59 into which disc 58 fits in plunger-like fashion. Each plate 5'? and each of the end plates 5'." and 51 has two vertical side edges 65) (Fig. 3), extending downwardly from the horizontal center line of the plate, and two lugs 65 projecting one beyond each such edge. The lower faces of these lugs are alined and both lie in the horizontal center line of the plate. Each lug G! fits into a short notch in one of the links Q3 or M, and into a long notch in the other link, being supported by both links. The plate is so formed as to clear the links 4! and 42. These lugs 6!, when their lower faces rest on the bottoms of the notches in links 43 and M, support the plate so that its center line lies in the same horizontal plane as the center line of the ram. The edges 60 slidably engage the inner vertical faces of the rails and thereby the center line of the plate is located in the same vertical plane as the center line of the ram. The rings 53 are also provided with supporting lugs one on each of two opposite sides thereof, and each such lug is of L- shapcd form with an outer part to rest in the notches of links ti and 422 and an inner part which overlies and clears the links 43 and 44. The lower faces of lugs 52 lie in the horizontal center line of the ring and thus when these lugs are seated in the notches of the links, the ring has its center line located in the same horizontal plane as the center line of the ram. Each ring also has two vertical sides 63 which lie closely adjacent one to each rail 3% and locate the ring laterally in close alinement with the ram but since the plunger disc 53 is engaged in the ring and fixed to plate 5? which is accurately alined as described, the plunger will aline the ring.

The first plate 51 of the series is fixed (Fig. 6) to the outer end face of the follower 33. A similar plate 51 is fixed to the abutment 56 of the resistance head 25 but the plate 511 has no plunger disc 58 fixed to it. All of the plates 5'! and the plate 5'5 are interconnected by a linkage made up of the two inner rows of link blocks 43 and M. This linkage enables the plates to be separated by the action of ram 28, when moved to the left on its return stroke, and limits the extent of separation of the plates and secures uniform spacing of the plates when the ram is drawn back as far as possible, The first plate 5'l of the series has its lugs 8i resting one in each of the long notches 55 of a pair of links 44, free for limited longitudinal movement relatively thereto. The short notches 54 of these links receive and closely fit the lugs SI of the next succeeding plate of the series, whereby the latter is held against longitudinal movement rel atively to this link. The lugs 50 of the second plate of the series also extend one into each of the long notches 53 of the links 43 in the adjacent row and can move longitudinally relatively thereto. The third plate 5'! has its lugs engaged in the short notches of links k and also in the long notches of a second pair of links M, the short notches of which are engaged by the fourth plate 5! and so on until the plate 57 is reached, the lugs of which fit in the short notches 54 of links M. There are ten links 3-25 and ten links M, and except for the end plates 5'1 and 51 each plate is supported by two links and engaged in a short notch in one and a. long notch in the other. The plates 51 and 51 being fixed to a follower 33 and head 2i, require no other support. When the ram is drawn back (to the left) the first plate 51 of the series moves with it.

Eventually the lugs of such plate strike the left hand end walls of the long notches 55 of links 44 and these links and the second plate then move with the ram. When the lugs of the second plate engage the left hand end walls of the long notches 53 of links 43, the latter are moved and with them the third plate of the series. As the ram moves to the left, the plates are successively brought into motion, as the lost motion in the link connections between succeeding plates is taken up, until finally all the lost motion in all the link connections is taken up, when the ram is stopped. The several plates are then uniformly spaced and positioned as shown in Figs. 6 and 7.

The'rings 59 are similarly interconnected by a linkage composed of ten links 4! and nine links 42, each ring except the end ones having its lugs 62 engaged with a link Bl on a link 42, such lugs fitting into a long notch of one and a short notch of the other. One end ring 59, the first of the series, has its lugs 62 engaged in the short notches 48 of links 4|. This same ring also has each of its lugs 62 closely fitting in notches formed one in the upper face and near the right hand end of each of a pair of long links 65. The links 65 slide in the same grooves as links 42 and at their left hand ends have rack teeth 66 formed in their upper faces. The other end ring 59, the last of the series, has its lugs 62 engaged in the long notches of the last pair of links 4! of the series These lugs also closely fit in notches formed one in each of a pair of long links 6? which slide in grooves in the narrow portions 41 of rails 39. The right hand ends of links Bl have rack teeth 68. This ring linkage, like the plate linkage, serves to limit the extent to which the rings can be drawn apart and maintains them uniformly spaced. For a reason to be later described, the rings move back with the plates when the ram is drawn back to its extreme left hand position. All the lost motion is then taken up in the linkage for both rings and plates. While the ring linkage is thus stretched out to'the limit, it may be moved first to the left and subsequently to the right, thereby moving all the rings 59 back over their respective plunger discs 58 and subsequently restoring them.

For the purpose of thus moving the rings 59 relatively to their respective plates 5'! and plunger discs 58, hydraulic means are provided, mounted in part on the follower 33 and in part on the resistance head 25 (Figs. 6 and 7). Rotatably mounted in ball bearings in the follower 33 (Fig. 6) is a horizontal shaft it which extends transversely through the follower and projects beyond both sides thereof. The ends of shaft it overlie the rails 39 and support the described ram-supporting rolls 40, which are mounted on ball bearings on the shaft. Fixed one to each of the extreme ends of shaft H! are gears H, which mesh one with each of the racks 5B. This shaft has fixed thereto a gear '52 (Figs. 6 and 7) located in a recess in the follower 33 and meshing with a rack 73, fixed to a slide it which is mounted to slide vertically in ways formed in the rear end of the follower. The slide is held in place by a plate 55 secured by cap screws lit to said end of the follower. The follower has an upstanding bracket ll (Fig. 7) to which is secured by screws 78 a cylinder 79, having therein a piston 80,-the rod 8! of which extends downwardly and has it lower end slotted to receive theupper end of slide 74 which is secured thereto by a pin 82. Liquid under pressure may be admitted to the lower end of the cylinder beneath piston till through a pipe 293 and a flexible hose 2%. The upper end of the cylinder is open to the atmosphere through suitable pipe connections indicated in part at 82. Thus, the piston may be raised by hydraulic pressure to effect movement of the ring linkage and all the rings to the left. This hydraulic motor is single acting. No pressure liquid is admitted to the upper end of the cylinder which normally contains nothing but air.

The return movement of this linkage is effected by a similar, single-acting hydraulic motor, the cylinder 85 of which is secured by cap screws 8E5 to a bracket 81, upstanding from the resistance head 29. This cylinder contains a piston 88 having a rod 88 connected to a slide 98 mounted to slide vertically in ways formed in head 2! and held in place by a plate ill and screws The slide carries a rack 93 which drives a gear 9 3 fixed to a horizontal shaft 95 which is mounted in ball bearings in head 2! and extends transversely therethrough. The ends of shaft 93 project beyond opposite sides of head 2! and have fixed thereto gears 98 which mesh one with each of the described racks 68. Liquid under pressure may be admitted to cylinder 85 beneath the piston 83 to raise the same and, through the connections described, shift the ring linkage to the right, restoring it to the position occupied prior to the movement of it by the piston 80. The upper end of cylinder 85 is connected to atmosphere. Movement of piston 88 upwardly pulls piston 853 downwardly and vice versa.

There are provided in connection with each of the press units, spacer fingers. These fingers are movable from an active position, wherein they lie between the plunger-bearing face of the plate M of the unit and the adjacent face of the ring 59 of the unit and prevent inward movement of the plunger 58 in the ring, to an inactive position wherein they are completely withdrawn from said position and enable the plungers to move inwardly in their rings for the pressing function. These fingers are provided in upper and lower sets, there being an upper and a lower finger for each press unit. The two sets of fingers are alike in construction and mounting and they are operated by similar means, wherefore only the upper set of fingers and their associated parts will be described and corresponding parts of the lower set will be designated by the same reference numerals with the addition of a prime.

The upper fingers are marked 9? and all of them are mounted on a bar of non-circular cross section which is conveniently square, such as shown at 98. Each finger has the form of a portion (somewhat less than half) of a hollow cylinder, the curvature of which is such that the fingers, when in active position, are substantially coaxially disposed with reference to the press units. Each finger is connected by an arm 99 to a substantially U-shaped yoke lllil which slips over the finger bar and slidably engages three of the four faces thereof. The fourth face is engaged by a roll till mounted between the two legs of the yoke and held in place by a screw E92. By removing the screw and roll the finger may be slipped off the shaft. By this provision for quick and convenient mounting and dismounting, fingers of one width may removed and others of a different width substituted, as is often desired. Each arm 69 at a location near its yoke me has a finished pad H33 adapted to engage one face of a plate 51. Secured by screws N34 to .voke Hill is a short arm or clip Hi5 adapted to engage the opposite face of the same plate El. The rear upper corner of plate 51' is engaged between the parts i613 and 595 in all positions throughout the range of normal swinging movement of the finger Ql. Therefore, when the plates El are moved axially, they will cause the fingers 91 to move axially along the finger bar 98, thus retaining each finger in proper axial position with reference to its plate. The fingers 9i are similarly engaged with the lowe' rear corners of plates 51. The finge s swing through an arc of somewhat niore than 90 from their active positions, shown by full lines to their inactive positions shown by dotted lines. When the fingers 91 are in their inactive positions, they may be removed from the bar 98 which turns them by a vertically upward pull after the screws H12 and rolls l lll which retain them on the bar have been removed, and it is not necessary to first remove the clips I85.

In the case of the lower fingers 91, the U- shaped yoke ltd of each is mounted at right angles to the arm 9% and engages the top and both side faces of bar 93, the better to support the weight of each finger. To remove each lower finger, its clip ltd, screw E52 and roll lEll are first removed. Then the finger il'l', if in its inactive position, may be moved laterally to the left far enough to with raw its yoke I66 from shaft 98, after which the finger can be drawn downwardly.

The finger bar $3 at its ends is formed with trunnions lfifi which are rotatably supported by ball bearings llll. One of these bearings is mounted in a cylindrical case 598 (Fig. 11) secured by screws N39 to the inner end face of the resistance head. The case 88 has a flange Hi) which with the adjacent face of head it retains the bearing in proper axial position. The other bearing (Figs. 4 and 5) is mounted in a case lil secured by screws Hi? to a plate it which in turn is secured by screws 25 to the inner end face of head 29. Adjacent the trunnion M6 in case ill, the finger bar 98 has cylindrical part M3 to which is fixed a pinion lid. The shoulder on bar 98 formed at the junction of the part i l3 with the adjacent trunnion Hi6 cooperates with the adjacent end face of plate Q23 to retain the bearing in position axially. The case H! is formed with ways in which a slide l l5 is mounted. This case has a removable cover H6 which is secured to case ill by screws i128 and which enables the slide to be slid into the ways, the ways being in part fo med in this cover section. The slide H5 carries a rack Ill which meshes with pinion l 54. One end of the slide 2 iii fits into a slot in the forward end of a piston rod H8 and is fixed thereto by a pin H8. The rod H3 has fixed to its inner end a piston iii! which slides in a cylinder i2l to opposite ends of which liquid under pressure may be admitted or exhausted through the pipe connections indicated at Elli and 2&2 in Fig. 2, whereby the fingers Ql are positively moved in both directions. The cylinder lift is secured by screws 323 to plate E24. The lower cylinder IN is mounted on a plate I23 which extends across between the standards 23 and is secured by bolts l2? thereto and by screws M9 to head 29.

Referring now to Fig. 6, each plunger disc 58 is secured, as by rivets 5353, to one face of a plate 57, the first disc 58 of the series being fixed to plate El which is imperforate. Except for plate 51 all the plates and discs are perforated, each having a large number of small holes l3! arranged in a plurality of circular series (Fig. 3). That face of each disc 58 which abuts a plate El is formed with a plurality of coaxially-disposed circular grooves 532 each serving to interconnect all the holes of one series. The face of the disc 58 which abuts plate 5'5 is similarly formed. In a lower sector of each disc are several radial grooves H23 (Fig. 3) for connecting the circular grooves 32 to the lower porti .1 of the outer periphery of the disc. Each disc 58 and each plate ill and plate 57 carries a suitable filter pad (Fig. 8), one on each of the exposed and nonabutting faces of each. These pads may consist of an inner screen 535 of relatively coarse mesh and an outer screen 35 of very fine mesh. The filter pad in the disc is held in place by inner and outer rings i353 and HEY, secured by screws A. suitable packing L39, such as camel hair, is mounted beneath the inner screen and held in place by the outer ring 53?, such packing serving as a peripheral seal between the plungerlike disk and the ring in which it slides. The filter pad on the plate 5'. is held in place by inner and outer rings Ml] and M8, respectively, secured to the plate by screws M2. This pad is mounted in a large circular eccss in the exposed face of the plate and projects slightly beyond such face. The outside diameter of the pad is larger than the inside diameter of the ring so that the pad will be clamped between the 'ing and plate to seal the joint ther-ebetwcen. The plate 57 (Fig. 6) carries no filter pad. The plate 57 is like plate El except that the face, which abuts head is formed with circular and radial grooves like the grooves I32 and I33.

Each lower finger 9'? along that portion of one of its inner edges, which portion underlies the outer ends of the several radial grooves i315, is bevelled as at 23. There are several holes Hi l through each finger Ell" leading from the inner to the outer face thereof. Each such hole at its inner end is connected by a groove Hill to the bevelled edge 53. The purpose of these provisicns is to conduct the cocoa butter (extracted during the filling operation) from the radial grooves allowing a free downward flow into the underlying receiving pan.

The liqu r, from which the cocoa butter is to be extracted is pumped into the several rings through an axial passage ltd (Fig. 6) in the re sistance head 2%. The usual valve 55% mounted in said head controls said passage. That portion of the passage extending from the valve ifii through the pressure abutment 555 and the plate 5i fixed thereto is tapered, diverging toward the ram. Each plate 5? and its attached disc 58 is formed with an axial passage l5?! similarly tapered. The disc 58 which is fixed to plate 5'5 as no passage such as 552. The tapered portions facilitate removal of the plugs of cocoa that remain therein after the pressing operation has been completed and the cocoa cakes have been removed. On a succeeding operation, the liquor pumped into the press will blow out all these plugs into the adjacent rings 59. That portion of each ring 59, which receives the pressed cake, is preferably tapered as at E5 3 to facilitate ejection of the cake.

The control of the several hydraulic cylinders described is effected by a series of valves mounted in a blcclr ids (Figs. 1 and 2), secured to one of the plates on head Ell. This block has two spaced longitudinal passages lfiil and 16! (Fig. 9),

iii)

extending from the left hand end of the block inwardly toward but not to the right hand end. Passage I68 is for supplying liquid under pressure to the various cylinders and isv connected to a supply pipe I62 (Fig. l). Passage it! is for exhausting fiuid from such cylinders and is connected toan exhaust pipe H53. Fig. 9 shows the valve control for the left hand end of the ram cylinder 25. A vertical passage i6 2. leads from the level of the passages ltt and itl downwardly to the bottom of the block where it connects with a pipe I65 leading to said end of said cylinder. A branch passage I66, controlled by a valve it? leads from exhaust passage It! to passage I84. A branch passage its, controlled by a valve I69, leads from the pressure passage N50 to passage ltd. A similar arrangement is provided for the right hand end of cylinder 25, the pressure and release valves being marked ill and ill (Fig. 1), respectively controlling admission to and exhaust from a pipe 1596 (Fig. 2) leading to the right hand end of cylinder 25. By opening valves Hi9 and ill. and closing valves ltl and lit, the ram will be moved on its pressure stroke. By closing valves H39 and ill and opening valves it! and HG, the ram will be moved on its return stroke.

There are four other pressure valves, the stems of which project above the top of block E59 and four other release valves the stems of which. project from the side of the block. The pressure valves H2 and its control the admission of pressure fiuid to pipes 26! and 262 which lead to opposite ends of the finger-operating cylinders l2l and EN, which are connected together to operate simultaneously, and control the lowering and raising, respectively, of the fingers. The release valves H4 and H75 control exhaust through pipes 2M and 2&2 from the same ends of cylinders l2l and iii which are controlled by valves ill and H3, respectively. Thepressure valves H9 and ill control admission of fluid to pipes 298 and 255, respectively, and thus to the link operating cylinders it and 85 respectively, and the corresponding release valves marked H8 and H2, control exhaust from said cylinders through pipes 2M and 2&5 respectively, the cylinders l9 and 85 being single-acting. The cross section shown in Fig. 9, showing the companion pressure and release valves it! and itdis typical of the five other sets of companion pressure and release valves.

A safety valve (shown in detail in Fig. 10) is provided to prevent damage by the ram on its forward stroke in the event that the ram is operated while the various rings 59 are empty or insufiiciently filled. Fixed to the top of one of the tie bars 22 is a valve body fist into which leads a pipe liii extending from the pipe ltfi. An exhaust pipe Hi2 leads from the body Hill. Within the body is a passage I83 controlled by a valve EM and adapted to interconnect pipes l8! and it? when valve R84 is open. This valve is nor-' mally closed by a spring 585 and is adapted to be opened only when an abutment I36 (Fig. 1) on follower 33 engages and moves the stem Hill of the valve. The parts are so located that the valve will be opened before the piston 23 can abut head 29. The opening of the valve serves to bleed the pipe E65 through which pressure liquid is conducted to the left hand end of cylinder 25 and thus stops the ram if it exceeds a predetermined outer limit on its pressure stroke.

The operation of the press will next be described. Assuming that the parts occupy the relative positions shown in Figs. 1, 2 and 3, the press is ready for filling. That is, the several press units are clamped together between the follower 33 and the abutment 56 on head 2! by pressure applied to the left hand end of the piston 26 of the ram. Liquid, such as oil, under pressure of around 1200 lbs. per sq. in., is admitted to the left hand end of cylinder 25. The fingers 91 and 5'5 are in active position and space apart the plates ii? and rings 59, whereby each plunger disc is held against inward movement in its ring and in a retracted position such as is shown in 8. The valve MI is then opened and the liquid, for example chocolate liquor, is pumped in through the passage I50 in head 2i to and through the central holes I52 in the discs and plates until all the chambers within the rings 58 are filled. As pressure builds up in these chambers, the filtering process begins, cocoa butter being expressed through the filter pads I34, E35 and being conducted through the holes l3l in the discs and plates into the grooves I32 and itt and through the holes Hi l in fingers 91', to fall into an underlying pan N39. The pumping of liquor continues \until sufficient cake-forming mass has been built up in the rings.

When one has extracted all the butter which it is possible to extract in this way, the valve Hill is closed and pumping of the liquor is stopped. Then the pressure on the ram is relaxed enough to allow the plates El and rings 59 to separate slightly in an axial direction and release the clamping pressure on the fingers 91 and 9'! to enable them to be moved into their inactive positions (shown in dotted lines in Fig. 3) by the application of liquid under pressure to the left hand ends (as viewed in Fig. 3) of cylinders 12! and i2 l For separating the rings and plates for this purpose, the ram may be positively moved to the left by liquid pressure admitted to the right hand end of cylinder 25. Sometimes, however, this may not be necessary because when the pressure in the left hand end of cylinder 25 is allowed to drop below the pressure of the liquor in the chambers of the discs, the plates and rings tend to spread apart by the expansion of the liquor in said chambers to a degree sufiicient for the purpose. The spacing fingers having been withdrawn, liquid is pumped into the left hand end of cylinder 25 to drive the several plunger discs into their rings for the purpose of extracting further cocoa butter by hydraulic press action. A very heavy pressure is needed for this purpose, the unit pressure in cylinder 25 being run up to around 6560 lbs. per sq. in. at the end of the pressing operation.

When all the butter that it is possible to extract in this way has been expressed, the ram is moved back as far as possible (until follower 33 abuts head 29 as shown in Fig. 6) by releasing pressure from the left hand end of the cylinder 25 and admitting pressure into the right hand end thereof. This causes the series of plates consisting of 57 5'1 and 57 to be spread apart sufficiently so that there is created between the filter pad carrying face of each plunger disc 58 and the plate 5i of the next succeeding press unit, a space of an axial length greater than that of the pressed cake within the disc. As the ram moves back, the first plate 51 fixed thereto, moves with it and carries along the attached plunger disc 53 of its unit together with the ring 59 and the pressed cocoa cake contained within such ring. The adhesion of such cake to the plate 57 of the next unit is broken and the cake remains substantially unmoved Within the ring,

adhering to the ring and plunger disc which together present to the cake a greater area of surface than does the plate 5?. So the ring 58 of the first press unit together with the cocoa cake is drawn along with plate 57 and plunger disc 58, the ring and disc retaining their same relative positions. The plate of the second press unit is next moved, being picked up and moved by the links and carrying with it its ring and the cocoa cake therein. As before, the ring 5?) travels vith the plate Ell because of the adherence of the cocoa cake to the ring 59 and to the plunger disc 53 or plate 5's. The plate 5'! of the third press unit is next moved, being picked up and moved by the links 33 and carrying with it its ring and the cocoa cake therein, and so on until all the plates 5? have been moved and all the cocoa cakes have been pried from plates iii. The plates 51, 57 uniformly spaced, as shown in Fig. 6, and the plates til and 5'3 have been moved axially away from the cocoa cakes, theretofore adhering to them, to allow room for the cakes to drop when the 1""- s 53 are subsequently moved back over the cakes. The linkage which interconnects the plates is drawn taut and held so by pressure on the righ hand end of piston 25. The linkage interconnecting the rings is likewise drawn taut. Then pressure is applied to the lower end of cylinder is (Fig. '7) to raise piston 33 and draw the taut linkages, which interconnect the rings, to the left, thereby moving all the rings toward their respective plates and completely telescoping them over their respective plunger discs 53, leaving the cocoa cakes unsupported whereupon they all drop. As the rings 5d are thus moved, the cakes are disturbed and their hold on plates 5'5 is probably loosened. In any event, as soon as the rings are completely drawn back, all the cakes drop by their weight. They are, as usual, received in an underlying pan such as 599.

After the cocoa cakes have been dropped out of the press, it is necessary to reposition the parts for anoth r operation. The first step is to admit pressure liquid to the lower nd of the cylinder 35 to raise its piston 58 and through the gears 96 and rack G8 to shift the linkage for the rings 59 to the right until each is rawn away from the plate of its press unit and into abutment with the plate of the next unit. The parts are thus restored to the positions shown Figs. 8 and 7. Pressure liquid is then admitted to the right hand ends of cylinder lfil and 225 (Fig. 3) to cause the fingers 8'5 to move back into active and spacing position. Then pressure liquid is admitted to the left hand end of cylinder 25 to cause the ram to move forward and clamp the press units together in position for filling. In the next filling operation, the chocolate liquor entering the press under heavy pressure will blow out the plugs of cocoa cake which remain in the holes i512 and in the outlet portion of the passage lfitl. These plugs remain in collecting chambers formed within the rings and become mixed with the liquor pumped into such chambers.

It is to be noted that the ring linkage operates on the return stroke of the ram as if the end. links were fixed to follower 33. Considering Fig. 7, as the ram moved to the left into the position shown the links had to move in unison with it because the piston 83 cannot move down in its cylinder as would be necessary for the purpose. Neither can the piston 88 move down in its cylinder because all the space in the cylinder below the piston is filled with oil and the valve controlling the exhaust from the lower end of the cylinder is closed. Thus, one end of the rink linkage is for all practical purposes fixed to head 24 and the other end is fixed to the ram except in the initial part of its return stroke. The reason for this qualification will be clear from an inspection of Fig. 7. Assume that the ram is to move forward (to the right) there must, in order to force the first plunger 58 into its ring 59, be relative movement between that ring and the follower So, as the ram advances, the racks 66 will move to the left and, turning gears H and E2, will raise the piston 86 slightly in its cylinder. Therefore, as the ram commences its return stroke, the racks it will not move with the follower 33 until the piston 88 again moves back into the position shown.

It will thus be seen that the entire operation of the press is effected automatically under manual control by the several valves described. The press units remain in place in the press and all the operator has to do is actuate the valves in proper sequence at the proper times. The heavy labor formerly necessary, including prying successive press units apart and prying the rings on" the plunger discs so that the with cakes therein, could be manually removed from the press so that the operator could crack up the cocoa cake with a mallet to free it from the ring, has been eliminated. The work can be accomplished more quickly, more neatly and with a minimum of labor. The rings, plates and discs will have a longer useful life because they are not removed and not subjected to the rough handling which is liable to injure them.

It is frequently desired to produce cocoa having different percentages of cocoa butter. Breakfast cocoa, for example, needs a higher percentage of cocoa butter than cocoa used for flavoring ice cream, for example. To vary the cocoa butter content, I substitute fingers of different width so that a cake of diiferent thickness will be produced. More cocoa butter can be expressed when the residue cake is thin and such cake will be drier. The arrangement described above enables the fingers to be quickly and easily removed from their bars and other fingers substituted. I prefer to make the fingers of aluminum or the like to secure light weight, which is desirable both for easy handling manually and for actuation automatically with less power.

The linkages described which interconnect the rings and those which interconnect the plates serve also as shoes for slidably supporting the plates and rings from the rails 39. They present bearing surfaces of substantial area as compared with that which would otherwise be available if,

following prior practice, the lugs iii and G2 rested directly on the rails. The weight of ring and plates is distributed over a greater area so that the pressure per unit of area on the rails is much less than formerly. The plates and rings slide more smoothly on the rails and are maintained in the desired erect positions and cannot easily be tipped out of such positions.

The power operated linkage for shifting the rings relatively to their plunger discs is an im portant feature of the invention as is also the linkage forseparating the plates on retraction of the ram. The automatic removal of the cakes is effected wholly automatically and expeditiously, no manual effort being required other than to operate the necessary control valves.

What I claim is:

1. In a press, a plurality of filter-carrying members, a plurality of rings, said rings and members being coaxially disposed in column formation, each ring cooperating with a pair of members to form a closed chamber and movable axially relatively to one member of such pair, means for filling said chambers with liquid to be filtered, means for moving the members of each pair toward one another and for subsequently spreading them apart, linkage means interconnecting the several rings and enabling them to move toward one another when said members move toward one another and being extended and drawn taut when said members are fully spread apart, and means for moving said linkage means first in one direction to cause each ring to become completely telescoped over one of the members with which it cooperates and subsequently in the opposite direction to restore the rings to their original positions.

2. In a press, having a pressure head formed with a hydraulic cylinder, a ram in said cylinder, and a resistance head; a column of press units disposed in coaxial relation and mounted between the ram and resistance head, each unit comprising a ring and a pair of cooperating filter-carrying members one of which is movable as a piston in the ring, linkage means interconnecting all said members and connected at one end to said ram and at the other to said resistance head, said linkage means enabling movement of said mem bers toward one another, means for moving said ram in one direction to shorten said column and move each member into its ring for the pressing action, means to move the ram in the opposite di rection to elongate the column and spread apart said members until said linkage means is drawn taut, a second linkage means interconnecting said rings and being drawn taut when the first linkage means is drawn taut, said second linkage means enabling the rings to move toward one another when the ram is moved in the first-named direction, and means located in part on the resistance head and in part on the ram for reciprocating the second linkage means.

3. In a press, having a pressure head formed with a hydraulic cylinder, 3, ram in said cylinder, and a resistance head; a column of press units disposed in coaxial relation and mounted between the ram and resistance head, each unit comprising a ring and a pair of cooperating filter-carrying members one of which is movable as a piston in the ring, linkage means interconnecting all said members and connected at one end to said ram and at the other to said resistance head, said linkage means enabling movement of said members toward one another, means for moving said ram in one direction to shorten said column and move each member into its ring for the pressing action, means to move the ram in the opposite direction to elongate the column and spread apart said members until said linkage means is drawn taut, a second linkage means interconnecting said rings and being drawn taut when the first linkage means is drawn taut, said second linkage means enabling the rings to move toward one another when the ram is moved in the first-named direction, means located in part on the resistance head and in part on the ram for reciprocating the second linkage means, and means for actuating said reciprocating means to positively move the second linkage means first toward the ram to telescope each ring on one of its members and then in the opposite direction to return the rings to their former positions.

4. In a press, having a pressure head formed with a hydraulic cylinder, a ram in said cylinder, and a resistance head; a column of press units disposed in coaxial relation and mounted between the ram and resistance head, each unit comprising a ring and a pair of cooperating filter-carrying members one of which is movable as a' piston in the ring, linkage means interconnecting all said members and connected at one end to said ram and at the other to said resistance head, said linkage means limiting the extent of separation of said members and enabling movement of them toward one another, means for moving said ram in one direction to shorten said column and move each member into its ring for the pressing action, means to move the ram in the opposite direction and spread apart the members until said linkage means is drawn taut, a second linkage means interconnecting said rings for limiting the extent of separation thereof on movement of the ram in the second named direction and enabling them to move toward one another when the ram is moved in the first-named direction, a hydraulic cylinder movable with the ram and having a piston connected to one end of the second linkage means, a second hydraulic cylinder mounted on the resistance head and having a piston connected to the other end of the second linkage means, the movement of the ram in the second-named direction drawing the second linkage means taut simultaneously with the first linkage means, means for actuating the first-named piston to draw the second linkage means toward the ram and completely telescope each ring over one of its members, and means for actuating the second piston to draw back the second linkage means and restore the rings to their former positions.

5. In a press, having pressure and resistance heads interconnected by a pair of laterally-spaced tie bars, a cylinder in the pressure head and a ram operating in said cylinder, together with a series of press units mounted in coaxial relation and in column form between the ram and resistance head and slidably supported from said bars; each unit comprising a ring and a plate having a plunger slidably engaged in the ring, said ram on its forward stroke movable toward the resistance head to shorten said column and force said plungers into the rings for the pressing action, means operable on the return stroke of the ram for separating the plates and uniformly spacing them one from the other, and links interconnecting each ring to the next ring of the series and each having hook-like parts for engaging the opposite and non-adjacent faces of the two rings which it interconnects and moving the one from the other during the return stroke of the ram and for enabling relative axial sliding movement of the rings the one toward the other during the forward stroke of the ram, means movable with the ram for drawing said links in one direction, and means on the resistance head for drawing the links in the opposite direction.

6. In a press, having pressure and resistance heads interconnected by a pair of laterally-spaced tie bars, a cylinder in the pressure head and a ram operating in said cylinder, together with a series of press units mounted in coaxial relation and in column form between the ram and resistance head and slidably supported from said bars; each unit comprising a ring and a plate having a plunger slidably engaged in the ring, said ram on its forward stroke movable toward the resistance head to shorten said column and force said plungers into the rings for the pressing action, means operable on the return stroke of the ram for separating the plates and uniformly spacing them one from the other, trackways provided one on each of the adjacent faces of said bars, two series of links one series for each trackway and each series supported on its traokway for sliding movement in a direction parallel to the of said column, said series of links interconnecting said rings one series on each side thereof, each link of each series extending between two successive rings of the series and having hook-like parts to engage the opposite and non-adjacent faces of such two rings, whereby movement of one ring will eventually cause ovement of the next ring or" the series during the return stroke of the ram and whereby to enable relative axial movement between the rings during the forward stroke of the ram, each trackway affording two parallel tracks for the series of links thereon and successive links of the series being located different tracks, means movable with the ram for drawing said links in one dir ction and means on the resistance head for drawing links in the opposite direction.

'7. In a press, having pr ssure and resistance heads interconnected by a pair of laterallyspaced tie bars, cylinder in the pressure head and a ram operating in said cylinder, together with a series of press units mounted in coaxial relation and in column form between the ram and resistance head and slidably supported from said bars; each unit including a pair of members which are relatively movable on the forward stroke of the ram to effect a pressing action, a series of links one on each side of said press units for interconnecting one of each pair to the corresponding members of adjacent pairs, each link having hook portions engageable with the opposite and non-adjacent faces of the two members which it interconnects and operable on the return stroke of the ram to limit the extent of separation of the last named members and cause one thereof to move the next, said links enabling the inte connected members to move toward one another on the forward stroke of the ram, the end links of the series having a connection one to the ram and one to said resistance head, whereby the return stroke of the ram spreads apart said members and uniformly spaces them, and trackways one on each tie bar f r slidably supporting said links.

8. In a press, having pressure and resistance heads interconnected by a pair of laterallyspaced tie bars, a cylinder in the pressure head, and a rain operating in said cylinder, together with a series of press units mounted in coaxial relation and in column form between the ram and resistance head and slidably supported from said bars; each unit including a pair or members which are relatively movable on the "forward stroke of the ram to effect a pressing action, a pair of parallel trackways provided on each tie bar, a series of links for each pair of trackways, each series interconnecting one member of each pair of press units to the corresponding members of adjacent pairs each. link having hock portions engageable with the opposite and non-adjacent faces of the two members which it interconnects and operable on the return stroke of the ram to limit the extent of separation of the last-named members and cause one thereof to move the next, said links enabling the interconnected members to move toward one another on the forward stroke of the ram, the end links of the series having a connection one to the ram and one to said resistance head, whereby the return stroke of the ram spreads apart said members and uniformly spaces them, alternate links of each series being mounted to slide in different trackways.

9. In a press, having pressure and resistance heads interconnected by a pair of laterally-spaced tie bars, a cylinder in the pressure head, and a ram operating in said cylinder, together with a series of press units mounted in coaxial relation and in column form between the ram and resistance head and slidably supported from said bars; each unit including a pair of members which are relatively movable on the forward stroke of the ram to effect a pressing action, a pair of parallel trackways provided on each tie bar, a series of links for each pair of trackways, each series interconnecting one member of each pair of press units to the corresponding members of adjacent pairs, each link having hook portions engageable with the opposite and non-adjacent faces of the two members which it interconnects and operable on the return stroke of the ram to limit the extent of separation of the last-named members and cause one thereof to move the next, said links enabling the interconnected members to move toward one another on the forward stroke of the ram, the end links of the series having a connection one to the ram and one to said resistance head, whereby the return stroke of the ram spreads apart said members and uniformly spaces them, alternate links of each series being mounted to slide in diilerent trackways, each said link having a first slot in which a portion of its member closely fits and by which it is fixed to such member and a second slot in which the next adjaceht corresponding member is engaged with freedom for the aforesaid relative movement.

10. In a press, having pressure and resistance heads interconnected by a pair of laterally-spaced tie bars, a cylinder in the pressure head, and a ram operating in said cylinder, together with a series of press units mounted in coaxial relation and in column form between the ram and resistance head and slidably supported from said bars; each unit including a pair of members which are relatively movable on the forward stroke of the ram to eliect a pressing action, a pair of parallel trackways provided on each tie bar, a series of links for each pair of trackways, each series interconnecting one member of each pair of press units to the corresponding members of adjacent pairs, each link having hook portions engageable with the opposite and non-adjacent faces of the two members which it interconnects and operable on the return stroke of the ram to limit the extent or" separation of said last-named members and cause one thereof to move the next, said links enabling the interconnected members to move toward one another on the forward stroke of the ram, the end links of the series having a connection one to the ram and one to said resistance head, whereby the return stroke of the ram spreads apart said members and uniformly spaces them, alternate links of each series being mounted to slide in different trackways, said members being supported through the intermediary of said links from said trackways.

ll. In a press, having a pressure head formed with cylinder therein, a ram in said cylinder, a 1" sistance head and a pair of laterally spaced tie bars interconn cting said heads; a series of press units each including a plate, a plunger fixed t0 the plate and a ring; said units mounted in coaxial relation and in column form between the ram and resistance head, said bars having trackways one on each paralleling the axis of the column of units, said plates and rings each having on opposite sides supporting lugs, and shoes of a length in the direction of said axis, greater than the axial length of said rings or plates and slidably supported on said trackways and in turn supporting through said lugs said rings and plates, said shoes arranged in two series one for said rings and one for said plates, each series having two rows on each trackway with the shoes of adjacent rows overlapping, the lugs of successive plates and rings fixed to shoes in different rows.

12. In a filter press, a pair of heads interconnected by tie bars and a ram operable in one of said heads, a series of press units slidably supported from said bars and mounted in column formation between the other head and the ram; each unit including a ring member, a plate member, a plunger carried by the plate member and movable in said ring member, a shaft non-circular in cross section and rotatably mounted at its ends in and extending between said heads, spacer fingers one for each press unit and each adapted to be moved into a position between the members of its units to limit relative movement thereof, said fingers supported on said shaft and slidable axially thereon in unison with one of the members of its unit, and means for swinging said shaft to simultaneously move said fingers into and out of said position.

13. In a filter press, a pair of heads interconnected by tie bars and a ram operable in one of said heads, a series of press units slidably supported from said bars and mounted in column formation between the other head and the ram, each unit including a ring member, a plate member, a plunger carried by the plate member and movable in said ring member, a shaft non-circular in cross section and rotatably mounted at its ends in and extending between said heads, spacer fingers one for each press unit and each adapted to be moved into a position between the members of its unit to prevent relative movement thereof, said fingers supported on said shaft and slidable axially thereon in unison with one of the members of its unit, and means for swinging said shaft to simultaneously move said fingers into and out of said position, each finger being mounted for convenient removal from said shaft and withdrawable radially therefrom when the fingers are moved out of spacing position.

14. In a filter press, a pair of heads'interconnected by tie bars and a ram operable in one of said heads, a series of press units slidably supported from said bars and mounted in column formation between the other head and the ram; each unit including a ring member, a plate memher, a plunger carried by the plate member and movable in said ring; a shaft non-circular in cross section rotatably mounted at its ends in and extending between said heads, spacer fingers one for each press unit slidably mounted on said shaft, each finger having an active spacing position in which it lies between the members of its unit to limit relative axial movement thereof and an inactive position in which it is withdrawn from the path of one member of its unit but still enaged with one face of the other member, a clip secured to each finger and engaging the other face of the last-named member and compelling the finger to slide on the shaft in unison with the movement of such member, and means for turning said shaft to move said fingers from one of said positions to the other.

15. In a press, having pressure and resistance heads interconnected by a pair of laterallyspaced tie bars, a cylinder in the pressure head, a ram operating in said cylinder, and a series of press units mounted in coaxial relation and in column form between the ram and resistance head and slidably supported from said bars; each unit including a pair of members which are relatively movable on the forward stroke of the ram to effect a pressing action, a series of links slidably supported for movement parallel to the axis of the press units, alternative links of the series being overlapped and slidable in different and non-interfering parallel paths, said links interconnecting one member of each pair to the corresponding members of adjacent pairs, each link extending between the two members which it interconnects and having hook-like parts for engaging the opposite and non-adjacent faces of such two members, the end links of the series being connected one to said ram and one to the resistance head whereby on the return stroke of the ram the interconnected members are successively moved and drawn apart into predetermined spaced relation and whereby movement of such members toward one another on the forward stroke of the ram is enabled.

16. In a press, having pressure and resistance heads interconnected by a pair of laterally-spaced tie bars, a cylinder in the pressure head, a ram operating in said cylinder, and a series of press units mounted in coaxial relation and in column form between the ram and resistance head, each unit including a pair of members which are relatively movable on the forward stroke of the ram to effect a pressing action, said bars having trackways one on each paralleling the axis of said series of units, one member of each unit having supporting lugs one on each side thereof, and shoes slidable on said trackwayson which said lugs are supported, each shoe having a length in the direction of said axis greater than the axial length of any of said members, said shoes arranged in two series one for each track'- way, each such series comprising two rows with the shoes of adjacent rows overlapping.

ALONZO LIN'ION BAUSMAN. 

